diff --git a/lib/g1/no_nodes_exception.dart b/lib/g1/no_nodes_exception.dart
new file mode 100644
index 0000000000000000000000000000000000000000..f83c6182e9e5cacad901c84034263d56501dcf76
--- /dev/null
+++ b/lib/g1/no_nodes_exception.dart
@@ -0,0 +1,5 @@
+class NoNodesException implements Exception {
+  NoNodesException(this.cause);
+
+  String cause;
+}